Project Summary/Abstract Supramolecular Bioorthogonal Nanozymes for Targeted Activation of Therapeutics In our proposed research we will create nanozymes?nanoparticles featuring protein-like size and surface properties that catalyze bioorthogonal processes using transition metal centers. These nanozymes will be used to activate prodrugs at tumor sites, using the bioorthogonal capabilities of the nanozyme to target tumors, generating therapeutics at the targeted tissue. We will assess these particles using in vitro models to determine intracellular therapeutic/imaging efficacy, targeting efficiency, and hemolytic properties. The particles will then be tested in vivo, assessing their efficacy in both imaging and therapeutic contexts. In our proposed studies, we will Aim 1: Fabricate nanozymes featuring different monolayer designs for optimizing particle loading and catalyst stability. We will quantify catalytic efficiency of these nanozymes for activating prodrugs, and determine their stability. Aim 2: Test the intracellular activity of nanozymes in cells through activation of pro- fluorophores and prodrugs. We will attach Her-2 targeting elements to the nanozymes and EGFR-targeting peptides to the polymeric prodrug delivery particles, and determine the ability to use dual AND targeting of nanozyme and carrier to target only cells that overexpress both receptors. Aim 3: Use targeted nanozymes to activate profluorophores and prodrugs at tumor sites using orthotopic breast carcinoma models. Aim 4: Differently targeted nanozymes and PEG/PLGA nanoparticles carrying prodrug will be used to provide therapeutic efficacy only at tumors overexpressing both targeted receptors, providing highly specific AND gate targeting. The goal of this research is to create therapeutic systems capable of high specificity through bioorthogonal chemistry. This research will build upon the supramolecular and nanomaterials strength of Rotello coupled with the cancer biology and animal model strengths of D. Joseph Jerry (UMass Vet. and Ani. Sci).